Dielectric barrier discharge (DBD) is the most efficient way used in industry for ozone generation. In last decades, many papers were published on such DBD-based ozone generators. Several geometric configurations can be used to generate ozone. They can be classified into two types depending on the discharge form: volume DBD, which is the common one in ozone industry, and surface DBD. Many studies have been conducted to analyze the ozone generation efficiency of both reactors to get maximum ozone production with the lowest possible power consumption. The aim of this paper is to carry out an experimental analysis of a patent-pending new reactor, of hybrid configuration, in which occur simultaneously a volume and a surface DBD. The hybrid reactor comprises a ground stainless steel cylindrical electrode, within which is placed a glass tube separated by an interval of 1 mm in which the volume DBD occurs. A second mesh stainless steel electrode connected to the high voltage is placed inside the glass tube wherein the surface discharge occurs. The obtained results showed a clear superiority of the hybrid reactor compared to both volume and surface DBD, in terms of the ozone concentration. The difference in the ozone concentration reaches up to 50% compared to the volume DBD and 30% compared to the surface DBD.

Volume Dielectric Barrier Discharge (DBD) is nowadays considered the most effective way for ozone generation in the industry. Some papers were published only on surface discharge reactors applied for ozone generation. This article describes an experimental investigation for the comparison between these two reactor types of ozone generation. Two surface and volume DBD reactors of cylindrical shape were used in the same experimental conditions. Obtained results showed that although the majority of ozone generators are of volume discharge type, the surface DBD presents significant superiority in terms of ozone generation and energy efficiency.

Ozone generation by dielectric barrier discharge (DBD) is widely used in industry. Several DBD configurations can be used to generate ozone, which are classified in two main types depending on the geometry of the electrodes: volume DBD and surface DBD models. The aim of this work is to conduct a comparative experimental analysis between surface DBD and volume DBD ozone generators having a cylindrical geometry. This comparative investigation is carried out not only in terms of ozone concentration and energy efficiency, but also in terms of cooling performance. Two experimental setups were used in this work, one for measuring the ozone concentration (in mg/L) and the ozone rate production (in g/h) and a second for cooling experiments. The obtained results show that although the volume DBD model is the most frequently used in industry, the surface DBD reactor gives better results in terms of ozone rate production and cooling.

Recycling of plastics from industrial wastes requires appropriate sorting technologies, such as the free-fall electrostatic separation of tribocharged granular materials. This paper introduces a novel electrostatic separation process characterized by the fact that the granules to be separated are charged in a fluidized bed affected by an electric field generated by two rotating roll electrodes. The experimental design methodology was employed for the modeling and optimization of the separation of a mixture composed of acrylonitrile butadiene styrene (ABS) and high-impact polystyrene (HIPS), originating from shredded obsolete computer cases. After processing the experimental data using the MODDE 5.0 software, the masses of ABS, HIPS, and middling collected after separation were expressed as quadratic functions of three of the control variables of the process: 1) duration; 2) speed of the fluidization air; and 3) high voltage applied to the electrode system. The obtained results demonstrate the effectiveness of this method for the separation of plastics from granular wastes.